Elevated blood eosinophil count is a valuable biomarker for predicting late acute cellular rejection after liver transplantation.

Background. Recent studies have indicated the value of increased blood eosinophil counts for the diagnosis of acute cellular rejection (ACR) after orthotopic liver transplantation (OLT). However, the relationship between eosinophil count and late ACR at more than 6 months after OLT is still unclear. Methods. We sought to retrospectively analyzed the ACR predictive value of eosinophil counts. In the day before or the day of biopsy among 40 biopsies performed on 37 patients beyond 6 months after OLT. Results. Relative eosinophil count was significantly higher in the ACR (n = 24) than the non-ACR cohort, albeit with no significant difference in absolute eosinophil count. Receiver operating characteristic (ROC) analysis showed an absolute eosinophil count of 0.145 x 10(9)/L and a relative eosinophil count of 2.3% to show the highest Youden index with area under the ROC curves of 0.746 and 0.813, respectively. When absolute eosinophil count >= 0.145 x 10(9)/L or relative eosinophil count >= 2.3% was defined to be elevated, the sensitivity and specificity to predict ACR were 45.8% and 87.5%, and 75% and 87.5%, respectively. When the absolute eosinophil count >= 0.285 x 10(9)/L or relative eosinophil count >= 3% was defined as elevated, the sensitivity and specificity were 25% and 100%, and 50% and 100%, respectively. All patients with an absolute eosinophil count >= 0.285 x 10(9)/L showed a relative eosinophil count >= 3%. Conclusions. Elevated blood eosinophil count was a valuable biomarker to predict late ACR after OLT.